Locking device for sharpeners.



(LM. KANAWAH. LoGKlNG DEVIGB fox SHARPBNBRS. APPLICATION FILED JAN. 5,1911.

Patented Jan. 27, 1914.

ffff UNTTED sTaTiis PATENT onirica.'

CRAWFORD M. KANAWAH, OF ST. LOUIS, MISSOURI, ASSIGNOR TO TWINPLEX MANU-FACTURIN G COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

LOCKING DEVICE FOR SHARPENERS.

Specication of Letters Patent.

Patented Jan. 27, 1914.

To (1U w/m/n it muy Concern Be it known that I, CRAWFORD M. KANA- WAH, acitizen of the United States, residing in the city of St. Louis, in theState of Mis souri, have invented certain new and useful Improvements inLocking Devices for Sharpeners, of which the following is aspecification.

My invention relates to locking devices for Sharpeners and refersparticularly to such devices used in connection with sharpeners forrazor blades.

lt is one of the objects of my invention to simultaneously secure aconstant predetermined pressure on each edge of the blade, and toaccomplish this result I provide a pair of rotatable sharpening elementswhich, by means of suitable gearing, are rotated in opposite directions.

The blade is mounted in a blade holder, this blade holder rotatingthrough a half turn When Jdie sharpening elements attain certainpredetermined positions. In order to allow the blade to rotate, a recessis provided in each of the sharpening elements. My construction is suchthat the pressure eX- erted b v the blade on the sharpening elements isattained by the resiliency of the blade itself` the axis of rotation ofthe blade being always the saine.

further object of my invention is to prevent` the possibility ofrotation of the blade except when the edges of the latter are oppositethe above-mentioned recesses in the sharpening elements and the bladeholder is being rotated by means presently to be described. This resultis accomplished by the use of a spring actuated paivl or other similardevice which preferably engages the pinion associated with the bladeholder. When the sharpening elements are in position for the blade to berotated, the pawl is released from such engagement by means of a cam ona gear sector which is mounted on one of the sharpening elements, thisgear sector engaging the pinion on the blade holder to effect therotation of the latter.

A still further object of my invention consists in so constructing thevarious parts that the blade Sharpener is capable of readydisassembling. This result is accomplished by mounting the sharpeningelements on shafts Which can be readily removed from said elements,these shafts preferably being ln the form of Wood screws which areremovably inserted in the sharpening elements. In order to remove theblade holder, I provide a shoulder on the same which is engaged by afriction spring, thereby forcing the blade holder longitudinally in thedirection of its own axis and holding it securely in position. lVhen thespring is disengaged from the blade holder, the same may move in theopposite direction a suiiicient distance to disengagc one end of theblade holder from the frame, and the blade holder may thus be readilyremoved. In order to accomplish this result more easily the aperture inwhich the end of the blade holder engaged by the friction spring iscontained is made slightly larger than the journaled end of the bladeholder. The friction spring above-mentioned also has the auxiliaryfunction of preventing-...free rotation of thc blade holder, shouldthere be a slight interval between the disengagement of lthe bladeholder pinion by the gear sector and engagement of said pinion by thelockmg pavvl.

ln the above general description of my in-l vention, I have mentionedcertain preferred forms of construction to obtain the desired results,but it will be evident to those skilled in the art that these resultscould readily be attained by changes of mechanical details.

These and other advantages of my invention will be more readilyunderstood by reference to the accompanying drawings which represent apreferred embodiment of my device and in which:

Figure 1 is a plan of the razor bladeV Sharpener. Fig. 2 is an endelevation of the parts shown in Fig. 1, a portion of the frame beingbroken away to show the interior mechanism. Fig. 3 is a vertical sectionon the line 3 3 of Fig. l. Fig. 4 is a perspective view of the bladeholder and blade adapted to tit therein. Fig. 5 is a partly perspectivevievvT and partly longitudinal section through one of the sharpeningelements showing the method of attaching the gear associated with eachsharpening element. Fig. 6 is a vertical transverse sec tion through thetwo sharpening elements, the blade holder and the razor blade. Fig. 7 isa' fragmentary longitudinal section through a portion of one of thesharpening elements. ig. 8 is a section similar to that shown in Fig. 6but with the sharpening elements in a different position.

lportion 31 adapted to fit The frame 15 of the razor blade sharpener hasa front wall 16 and a rear wall 17. 0n the front wall 16 are theinwardly projecting bosses 18, 18 and on the rear wall are thecorresponding bosses 19, 19. The sharpj ening elements 20 and 21 arelocated between the front wall 16 and the rear wall 17 and are held inposition by means of the shafts 22 and 23 which preferably consist ofwood screws each screw having a threaded portion 24 adapted to engagethe threads 25 in the aperture 26, extending longitudinally through eachof the sharpening elements. a clutch 27 adapted to be engaged by asimilar clutch 28 on the crank 29. The pin 28 extends from clutch member28 and fits in an aperture in the end of shaft 22. The shaft 23, on theother hand, hasan ordinary screw head 30 ou its front end. The rear endof each shaft consists of a journaled in a suitable openin each of thebosses 19 of the rear Vwall of the sharpener. As most clearly shown inFigs. 1, 5 and 7 each of the sharpening elements on its front end has aportion 32 of somewhat smaller diameter than the main part of thesharpening element. The object of having this portion 32 of lessdiameter is to allow more ready access to the parts which will later bedescribed.

, Mounted loosely on the shaft 22 and com" ing in contact with the frontend of the sharpening element 2O is the gear 33 which3 has a smallaperture 34 therein adapted to be brought in register with the pin 35which is held in the front end of `the sharpening element 20. It will beevident that the pin 35 serves to prevent rotation of-the gear 33independently of the sharpening element. Similarly a gear 36 is providedat the front ing y end of the sharpening element 21 being held inposition by a similar pin 35.

Extending between the front wall 16 and the rear wall 17 is the bladeholder 37 having near its front end the pinion 38, but having j ajournal portion 39 which has its bearing in the front wall 16 of theSharpener. s most clearly shown in Fig. 4, the main portion of the bladeholder is recessed to form the fiat surface 39a through most of itslength, the pins 40, 40 projecting upwardly from this flattenedsurface.' The clamping member 41 hinged at 42 is adapted to be broughtinto engagement with the flattened portion 39, the apertures 43, 43registering with the pins 40, 40. The rear end of the blade holder 'hasa journal 44 slotted-at 45, the extension 46 of the clamping member`41being adapted to lit in the slot 45 when the clamp 41 is brought intoclosed osition. It will now be apparent that the blizide 47 may beplaced on the flattened portion 39 of the blade, holder and securelyheld thereon by' fits, The shaft 22 has on its front end j closing theclamping member 4.1.

A spring 48 is fastened to the rear wall 17 of the sharpening member andat its free end is the curved portion 49 adapted to engage the journal44 of the blade holder 37 and also to abut against the shoulder 5() ofsaid blade holder, thereby preventing the latter from moving toward therear in the direction of its longitudinal axis. The locking member 51 ispivoted at 52 to the rear wall 17 and engages the top of the journal 44of the blade holder 37. The aperture in the rear wall 17, in which thejournal 44 is somewhat larger than this journal allowing movement of thesame in a vertical plane, and thus making it possiblel to readily swingthe locking member into its inoperative position, vWhen this is done, itwill be evident that the clalnping member 41 may be readily raised byits extension 46 and the blade 47 may either be removed from the bla-deholder or placed in position therein.

As best shown in Fig. 3, a pawl'53 `is l pivotally mounted on the frontwall 16 at 54 and is `normally held in engagement with one of the teethof the pinion 38 by means of the spring 55: The pawl 53 is preferablymade in the form of a bell-crank having the extending arm 56. Mounted onthe gear 33 is a gear sector 57 adapted to engage the teeth of thepinion 38. This gear sector also has a cam surface 58 adapted to engagethe arm 56 of the pawl 53, thereby removing the latterfrom engagementwith the pinion 38.

Each of the sharpening elements 20 and 21 has a recess 59 in itsperiphery, the purpose of which will be explained hereafter. Eachsharpening element is also covered with a strop 60 of leather or othersimilar material.

One of the advantageous features of my invention is the readiness withwhich 'the various parts can be disassembled. In order to accomplishthis it is only necessary to first move the locking member 51 out of itsoperative position and to'then. depress the upper end of the spring 48.`This being done, the blade holder 37 may be moved to the rea-r` untilthe shoulder 50 comes in contact with the rear wall 17 thereby removingthe journal portion 39 from its engagement with the front wall 16. Theblade holder may then readily be removed by first raising the front endof the same and then withdrawing the rear end from the rear wall 17. TheneXt step consists in removing the shafts 22 and 23 by unscrewing thesame f from the sharpening elements 20 and 21 respectively. This beingdone the sharpening elements' may themselves readily be removed fromtheframe 15.

` The operation of my improved razor blade sharpener maynow" be readilunderstood. The gear 33 is in mesh with t e that as the sharpeningelement 20 1s rotatejl,v f

by means of the crank 29, the sharpening element 2l will besimultaneously rotated in the opposite direction. The blade 47 havingalready been placed in position in the blade holder as previouslyexplained, it Will be evident, as most clearly shown in Fig. 8, that theedges of the blade are held in contact 'with the strop 60 of thesharpening elements by the resiliency of the blade itself. lVh en thesharpening elements 20 and 2l have been turned to such a position thatthe recesses at 59 approach the edges of the blade 47. the radius ofeach of the sharpening elements is gradually decreased as shown at (3lin order to prevent a sudden release of pressure of the edges of theblade. When the sharpening elements have been rotated sufciently so thatthe recesses 59 are opposite the edges of the blade 47, the cam surface58 engages the arm 56 of the pawl 53, thereby freeing the latter fromits engagement with the pinion 58, and the gear sector 57 then engagesand rotates the pinion 3S through a half revolution, thereby causing theblade 47 to turn Within the recesses 59, and bringing the oppositesurfaces of the edges of the blade into position to be engaged by thestrops 60 of the sharpening elements. It Will be evident that as soon asthe gear sector 57 is freedfrom engagement with the pinion 38, theIatter is positively locked in position by the pawl 53, rotation duringthe slight interval Which may occur being prevented by the spring 48.

It Will be clear to those skilledin the art that many changes could bemade in the preferred form of razor blade Sharpeners which I havedescribed Without departing from the spirit of my invention.

That I elainiisrl. In a razor blade Sharpener, the combination of a pairof sharpening elements ha ring recesses in their peripheries, means torrotating said sharpening elements, means for holdingr the blade to besharpened, a spring actuated locking pawl engaging said blade-holdingmeans during contact of said blade with said sharpening elements, andmeans for releasing said paWl When said blade is freed from contact Withsaid sharpening elements, thereby permitting rotation of the bladeWithin the recesses in said sharpening elements, substantially asdescribed.

2. In a razor `blade Sharpener, the combination of a pair of sharpeningelements having recesses in their peripheries, means for rotating saidsharpening elements, a rotatable blade holder having a pinion mountedthereon, a spring actuated locking pawl engaging said pinion duringcontact of said blade with said sharpening elements, means for releasingsaid locking pawl from said pinion when the recesses in said sharpeningelements are brought opposite the edges of said blade, and meansengaging said pinion for rotating said blade holder, thereby rotatingsaid vblade Within the recesses of said sharpening elements,substantially as described.

3. In a razor blade sharpener, the combination of a pair of sharpeningelements having recesses in their peripheries, gears mounted on saidsharpening elements and in mesh with each other, means for rotating saidsharpening elements, a blade holder for retaining the blade to besharpened, a pinion mounted on said blade holder, a spring actuatedlocking pawl normally engaging said pinion, means for releasing saidlocking pawl when the recesses in said sharpening elements are broughtopposite the edges of said blade, and a gear sector mounted on one ofsaidgears for enga-ging said pinion and rotating said blade holderduring the release of said locking paWl,Whereby the blade iscorrespondingly rotated within said recesses and the opposite surfacesof said blade brought into contact with said sharpening elements,substantially as described.

4. In a razor blade Sharpener, the combination of a pair of sharpeningelements having recesses in their peripheries, means for rotating saidsharpening elements, means for holding the blade to be sharpened, meansfor rotating said blade holding means, a spring actuated locking pawlnormally engaging said blade holding means, and means for releasing saidlocring pawl from said blade holding means during engagement of thelatter by said rotating means for said blade holding means,substantially as described.

5. In a razor blade Sharpener, the combination of a pair of sharpeningelements having recesses in their peripheries, means for rotating saidsharpening elements, a holder for retaining a blade to be sharpened,means for rotating said blade holder When the edges of said' blade areWithin said recesses, a spring actuated paWl for normally locking' saidblade holder against rotation, and means for releasing said pawl whensaid blade y holder is engaged by its rotating means, sub- `stantiallyas described.

CRAWFORD M. KANAWAH.

Witnesses:

THOMAS M. CAUBLER, W. A. RmDIoK.

